Journal of Gastroenterology

, Volume 41, Issue 4, pp 369–377

Farnesoid X receptor, hepatocyte nuclear factors 1α and 3β are essential for transcriptional activation of the liver-specific organic anion transporter-2 gene

  • Hideo Ohtsuka
  • Takaaki Abe
  • Tohru Onogawa
  • Noriko Kondo
  • Takeaki Sato
  • Hiroshi Oshio
  • Hiroya Mizutamari
  • Tsuyoshi Mikkaichi
  • Masaya Oikawa
  • Toshiki Rikiyama
  • Yu Katayose
  • Michiaki Unno
Article

DOI: 10.1007/s00535-006-1784-3

Cite this article as:
Ohtsuka, H., Abe, T., Onogawa, T. et al. J Gastroenterol (2006) 41: 369. doi:10.1007/s00535-006-1784-3

Abstract

Background

We isolated the human liver-specific organic anion transporter gene, LST-2 (OATP8/SLCO1B3), which is exclusively expressed in the basolateral membrane of the hepatocytes. In this study, we analyzed the transcriptional regulation of the LST-2 gene in hepatocyte-derived cells and the effect of bile acid.

Methods

Transcriptional activity of the LST-2 gene was measured using a human LST-2 promoter–luciferase reporter plasmid under various concentrations of bile acids. Electrophoresis mobility shift assays of farnesoid X receptor (FXR), hepatocyte nuclear factor (HNF) 1α, and HNF3β were performed.

Results

Luciferase analysis showed that the 5′-flanking region from −180 to −20 bp is responsible for LST-2 transcriptional activity. By site-directed mutation analysis, it was revealed that the consensus binding sites for FXR, HNF1α, and HNF3β play important roles in the transcriptional activity of the LST-2 gene. By electrophoresis mobility shift assay, we observed specific protein–DNA complexes of FXR, HNF1α, and HNF-3β. Luciferase activity was increased fivefold when chenodeoxycholate or deoxycholate were added. Northern blot analyses revealed that the expression of LST-2 was increased by addition of chenodeoxycholate or deoxycholate in a dose-dependent manner.

Conclusions

This study demonstrated that the transcription of the LST-2 gene is regulated by three transcription factors, FXR, HNF1α, and HNF3β. HNF1α and HNF3β might contribute to its liver-specific expression, and FXR might play a role in its transcriptional activation by bile acids.

Key words

organic anion transportertranscription factorbile acidHep3BTHLE-3

Copyright information

© Springer-Verlag Tokyo 2006

Authors and Affiliations

  • Hideo Ohtsuka
    • 1
  • Takaaki Abe
    • 2
    • 3
  • Tohru Onogawa
    • 1
  • Noriko Kondo
    • 1
  • Takeaki Sato
    • 1
  • Hiroshi Oshio
    • 1
  • Hiroya Mizutamari
    • 4
  • Tsuyoshi Mikkaichi
    • 3
  • Masaya Oikawa
    • 1
  • Toshiki Rikiyama
    • 1
  • Yu Katayose
    • 1
  • Michiaki Unno
    • 1
  1. 1.Division of Gastroenterological Surgery, Department of SurgeryTohoku University Graduate School of Medical ScienceSendaiJapan
  2. 2.Divisions of Nephrology, Endocrinology, and Vascular Medicine, Department of MedicineTohoku University Graduate School of Medical ScienceSendaiJapan
  3. 3.PRESTOJapan Science and Technology Corporation (JST)KawaguchiJapan
  4. 4.Division of Gastroenterology, Department of MedicineTohoku University Graduate School of Medical ScienceSendaiJapan